1. Field of the Invention:
The present invention relates to a sialosyl glyceride and a process for producing the same.
2. Description of the Prior Art
Many of diseases derived from lesions relating to the nervous system are intractable. The number of the remedies for these diseases are not so many. At present, ganglioside (trade name: Cronassial. Please see Japanese patent Unexamined Published application (hereinafter referred to as `J. P. KOKAI`) No. 52-34912), which is a natural glicolipid, and Mecobalamin (a kind of a vitamin) are clinically used.
However, the effects of them are yet insufficient and, therefore, the development of a more effective remedy has been eagerly demanded.
After intensive investigations made for the purpose of filling the demand, the applicant has developed sialosyl glycerolipids of the general formula: ##STR2## wherein R.sup.1 represents a hydrogen atom or CH.sub.3 CO--, R.sup.2 represents an alkali metal, a hydrogen atom or a lower alkyl group and n represents a number of 1 to 30
which are useful as remedies for the nervous diseases (Please see Japanese Patent Application No. 62-283491).
In general, natural compounds contain a higher ester bond content than ether bond content. However, the sialosyl glycerolipids have ether bonds in 1-position and 2-position of the glycerol. Therefore, these compounds not always have a sufficient compatibility with the living bodies and they are not always excellent with respect to the antigen-antibody reaction. In addition, since these compounds have the ether bonds, it is difficult to select a suitable protective group in the production of them. Thus, they cannot be easily produced for the above-described reasons.